stan/jdk-24
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

7037812: few more defaults changes for new AMD processors

Browse Source 
Use PREFETCHW as default prefetch instruction, set UseXMMForArrayCopy and UseUnalignedLoadStores to true by default.

Reviewed-by: kvn
This commit is contained in:
Tom Deneau 2011-04-19 09:30:17 -07:00 committed by Vladimir Kozlov
parent 7fb4bcc550
commit e8d2ed978f
1 changed files with 15 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
hotspot/src/cpu/x86/vm/vm_version_x86.cpp
View File

@ -441,12 +441,25 @@ void VM_Version::get_processor_features() {
}
}
// On family 21 processors default is no sw prefetch
if ( cpu_family() == 21 ) {
// some defaults for AMD family 15h
if ( cpu_family() == 0x15 ) {
// On family 15h processors default is no sw prefetch
if (FLAG_IS_DEFAULT(AllocatePrefetchStyle)) {
AllocatePrefetchStyle = 0;
}
// Also, if some other prefetch style is specified, default instruction type is PREFETCHW
if (FLAG_IS_DEFAULT(AllocatePrefetchInstr)) {
AllocatePrefetchInstr = 3;
}
// On family 15h processors use XMM and UnalignedLoadStores for Array Copy
if( FLAG_IS_DEFAULT(UseXMMForArrayCopy) ) {
UseXMMForArrayCopy = true;
}
if( FLAG_IS_DEFAULT(UseUnalignedLoadStores) && UseXMMForArrayCopy ) {
UseUnalignedLoadStores = true;
}
}
}
if( is_intel() ) { // Intel cpus specific settings